物化法强化厌氧消化去除污泥中PhACs的研究

Removal of Ph ACs from Sewage Sludge Using Anaerobic Digestion Process Enhanced by Physicochemical Treatment

针对污泥中典型的药理活性化合物(Ph ACs)——氯贝酸、三氯生、卡马西平和双氯芬酸,采用超声或快速机械转盘联合厌氧消化[中温:(35±2)℃、高温:(55±2)℃]工艺,通过GC/MS检测分析,研究其去除效果和特性。结果表明,当中温厌氧消化的污泥龄由10 d(高温厌氧消化系统为7 d)提高到20 d,中温厌氧消化系统对三氯生的去除率由44%提升至74%,高温厌氧消化系统则由52%提高到了74%;采用声能密度为0.05 W/m L的超声强化预处理30 min后,后置超声联合高温厌氧消化对目标物的去除率最高,分别为73%(氯贝酸)、76%(三氯生)、64%(卡马西平)、73%(双氯芬酸),尤其对通常认为较难去除的卡马西平,去除率较高温条件下的直接厌氧消化(去除率为56%)增加8%;采用前置和后置快速机械转盘(转速为100 r/min、处理2 h)与厌氧消化联合,对目标物的去除率有一定的提升,特别是后置转盘联合中温厌氧消化工艺,对双氯芬酸的去除率增加8%,去除率达到68%。

The anaerobic digestion （AD） process [ mesophilic condition ： （35 ± 2） ℃ and thermophilic condition： （55 ±2） ℃ ] combined with sonication or high-speed mechanical rotary disc treatment was used to remove the typical pharmaceutically active compounds （PhACs） including clofibrate, triclosan, carbamazepine and diclofenac from sewage sludge, and their removal effects and charactericstics were investigated by gas chromatography-mass spectrometry （GC/MS）. The results showed that when the sludge retention time for mesophilic condition was increased from 10 d （7 d for thermophilic condition） to 20 d, the removal rate of triclosan obtained in the mesophilic AD system was increased from 44% to 74%, and in the thermophilic AD system was increased from 52% to 74%. After ultrasonic pretreatment for 30 rain at the sound energy density of 0.05 W/mL, the removal rates of clofibrate, triclosan, carbamazepine and diclofenac by the thermophilic AD process with postpositional ultrasonic treatment were 73% , 76%, 64% and 73% , respectively. Especially for carbamazepine, which is regarded as difficult to be biodegraded, the removal rate increased by 8%. For the AD process combined with the rotary discs settled before or behind, the removal of the four compounds would be improved to a certain extent at the rotary speed of 100 r/min for 2 h. The removal rate of diclofenac was 68% with an increase of 8% in the AD process combined with the rotary disc settled behind.